高寒植物长鞭红景天种群生态位研究

Study on the Ecological Niche of Psychrophyte Rhodiola fasitiata Population

基于西藏色季拉山区高寒植物长鞭红景天分布的6个典型群落样地调查,采用定量分析的方法,研究了长鞭红景天所在群落中主要19种草本植物种群的生态位宽度、生态位相似比例和生态位重叠。结果表明:①分别用Shannon-weiner和Levins指数测得的主要草本种群的生态位宽度结果基本一致,长鞭红景天、中亚早熟禾、双花堇菜等种的生态位宽度值较高,分布在多种群落类型中,生态适应能力较强;②长鞭红景天与其他主要种群的生态位相似比例值为0.2000~0.7000,主要与生态位宽度值较大的种相似性比例值较大,与生态位宽度值较小的种相似性比例值较小;③长鞭红景天所在群落的生境地分异较大,各群落可利用的资源位较多,故长鞭红景天与大多数种群的生态位重叠较高,但相互间不存在较为剧烈的竞争。

Based on the sample plot survey on the ecological niche breadth of 6 typical communities with the distribution of psychrophyte Rhodiola fasitiata in Sejila Mountain area of Tibet, the ecological niche breadth, ecological niche similar proportion and ecological niche overlap of 19 main herbaceous plant populations in the con^nunity of R. fasitiata were studied by using the quantitative analysis method. The results of ecological niche breadth of main herb populations determined by Shannon-weiner and Levins were basically accordant. The ecological niche breadth of R. fasitiata, Viola biflora and Poa litwinowiana were higher. They were distributed in various types of communities and showed strong ecological adaptability. Tne ecological niche similarity ratio of R. fasitiata and other main species was 0.200 0 - 0.700 0. The similarity ratio was higher in the species of larger ecological niche breadth and that was lower in the species of smaller ecological niche breadth. The community habitat of Rhodiola fasitiata had greater difference and each community had abundant usable resources. So R. fasitiata had higher ecological niche overlap with most species, but there was no fierce competition among them.